Furnace



T. S. CURTIS.

FURNACE.

APPLICATION HLED DEC. I3, 1919.

1,405,762. Patented Feb. 7, 1922.

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FURNACE.

APPLICATION FILED 0501x1919.

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$4M @WM for RATION OF RHODE ISLAND.

FURNACE.

Specification of Letters Patent.

Patented Feb. '7, 1922.

Application filed December 13, 1919. Serial No. 844,545.

To all whom it may concern:

Be it known that I, THOMAS STANLEY CURTIS, a citizen of the United States, and resident of Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Furnaces, of which the following is a specification.

This invention relates to electric furnaces more particularly adapted for sintering or calcining ores, and composite massesof materials or producing a chemical reaction in such material, and the object of this invention is to provide such a furnace with means passing the material continuously therethrough while being subjected to a high degree of heat.

A further object of this invention is to set the hearth or work-supporting member of the furnace on an incline longitudinally and to provide means whereby this hearth may be tilted or rocked transversely in order that the material may be stirred and shaken and at the same time be given a predetermined speed of movement forwardly through the furnace, which speed of movement depends upon the motion imparted as well as the an 1c of inclination of the hearth.

further advantage of this rocking or shaking movement of the hearth portion is to roll the mass about and bring the different portions or particles thereof to the surface so that the heat may exert a more effective action upon the same and which agitation further serves to accelerate the liberation of the gases contained in the mass.

With these and other objects in view, the invention consists of certain novel features of construction, as will be more fully described, and particularly pointed out in the appended claims.

In the accompanying drawings:

Figure 1--- is a longitudinal sectional elevation showing one form of my improved furnace.

Figure 2 is a transverse sectional view on line 2-2 of Figure 1.

Figure 3 is a modification of the structure illustrated in Figure 1.

Figure 4 is a section on line 4-4 of Figure 3.

Referring to the drawings, 10 designates the elongated body portion of the furnace which is constructed of refractory brick or other material having high heat-resisting qualities. This furnace is provided with a heat chamber 11 having a hearth or bottom portion 12 therein on which the material to e treated is supported while traveling through the furnace. The opposite ends of thls heat chamber are partially closed by the end walls 13 and 14 for the purpose of protecting to some degree the supporting end plates 15 and 16, thereby leaving communicatlng passageways l7 and 18 which are substantially the same width as the heat chamber but of considerably less height.

These end plates 15 and 16 are recessed out forming communicating chambers 19 and 20, and in the end wall of each of these sup porting plates I have secured hollow trunnions 21, which are mounted to rotate in bearings 22, said bearings being supported 1n standards 28 each supported on its base 29, one of which bases is shown as being higher than the other so as to position the furnace on an incline for the purpose presently described.

The material is fed to the higher end of the furnace through the supply chute 30 supported by bracket 31 from the bearing 22, said chute communicating with the laterally elongated inlet opening 23 and after passing through the furnace drops into chamber 20 and is discharged through the opening 24. The preferred method of applying heat to this furnace is by mounting a series of oppositely-disposed pairs of electrodes 32 whereby the are formed between each pair causes the radiating heat to act upon and treat the material as it moves along the hearth, but I do not wish to be restricted to the use of heating by means of the electric are as any other convenient means for heating may be applied to my improved form of furnace.

In order to facilitate the treatment of the material while passing through this furnace have provided means for rocking, tilting or otherwise moving the furnace and the material while the same is passing through the connector 34 and frame 35, which crank is shown as being rotated by the pinion and gear 36 and belt driven pulley 37 but any suitable means for imparting a rocking motion to this furnace or its hearth, may be employed.

In operation it is only necessary to continuously deposit the material to be treated such for instance as magnesite, limestone or other ore or material into the chute 30, the rocking motion of the furnace serving to roll, move and agitate the material so that it will slide or roll along the surface of the hearth to be acted upon by the intense heat in the furnace. The rolling about, stirring and agitating of the charge causes new surfaces or portlons of the mass to be presented to the action of the heat and also serves to accelerate the liberation of the gases contained in the mass and after the charge has been acted upon sufficiently during its passage through the the chamber it finally works its way out and is discharged through the opening 24; the speed of the traveling charge through the furnace depends upon the combined effect of the inclination of the hearth and the action of the oscillating motions.

This so-called rocking hearth furnace may also be employed in the manufacture of black ash from which carbonate of soda may be leached according to the so-called Le Blane process; cement may be burned; fine concentrates or ore may be sinteredor clinkered; and any other material which is amenable to treatment at high tempera? tures and which will run over an inclined plane may be passed through the furnace.

Figures 3 and 4 illustrate a modified form of my improved construction in which the body portion 38 ofthe furnace is fixed and the hearth 39 is mounted to be rocked or moved therein. To accomplish this in a simle and effective way the hearth is mounted in bearings 40 on a pivot rod 41 which'rod is preferably formed hollow so that water may be passed therethrough to keep the bearings cool.

The hearth is shown as being adapted to be rocked by means of the crank 42 through connecting rod 43 and frame 44.

At the upper end of this hearth is mounted a supply chute 45 through which the material may be fed continuously to be deposited.upon this moving inclined hearth down which it rolls, slides or advances beneath the series of electrodes 46.

It will be noted, owing to the fact that the chute 45 in this furnace as well as chute 30 illustrated in Figure 1 is at the higher end of the furnace and that the exhaust gases in attempting to escape therethrough will heat the entering charge before it is deposited onto the hearth.

After the material has been sufiiciently treated by the heat it drops from the end of the hearth into the discharge chute 47.

The advantages of the type shown in Figures l and 2 over those shown in Figures 3 and 4 are first, that it is possible to attain a very much higher degree of temperature with a given expenditure of energy owing to the fact that the size of the chamber to be heated is smaller and there are no extended areas of cool walls to absorb the heat as the whole is being rocked. Then again the heat applied is radiated to the roof as well as to the charge on the hearth and the reflected heat from the roof serves to assist in heating the charge more uniformly. Another advantage is seen in the fact that this type of furnace can be practically completely assembled in the factory where it is made and shipped to a distant point in shape to set up and operate with a minimum of field work required.

The foregoing description is directed solely towards the construction illustrated, but I desire it to be understood that I reserve the privilege of resorting to all the mechanical changes to which the device is susceptible, the invention being defined and limited only by the terms of the appended claims.

I claim:

1. A furnace having means for passing the material to be treated continuously therethrough by transversely oscillating the mass of material therein, and means in the furnace for applying a. high degree of heat to the traveling material.

2. In a furnace, having an entrance and a discharge opening, an inclined hearth over which the material to be treated passes, means for imparting a transverse oscillatory motion to the hearth of the furnace to agitate the material thereon while being treated and to cause the material to advance over the hearth from the entrance opening, and means for. subjecting the agitated mass to a high degree of heat.

3. Ina furnace having an entrance and a discharge opening, an inclined hearth over which the material to be treated passes, means for imparting a transverse oscillatory motion to the hearth of the furnace to agitate the material thereon while being treated,

means for subjecting the agitated mass to a 4 high degree of heat said hearth being inclined downwardly from the entrance opening to the discharge opening, whereby the mass may be continuously advanced while being agitated.

4. A furnace having a hearth set on an incline, an entrance at the upper end of the hearth for the material to be treated and a discharge at its lower end, means for imparting a transverse oscillating motion to the hearth to agitate the material and cause it to move down the hearth in a substantially zig-zag path, and means for applying a high degree of heat to the moving charge.

5. In a furnace, a hearth set on an incline, openings in the furnace walls at both ends of said hearth through which material maybe continuously supplied, means for transversely oscillating the hearth, whereby the material is agitated and advanced through the furnace in a substantially zig-zag path over the hearth and discharged, and a plurality of sets of oppositely-disposed electrodes projecting laterally through the side walls of the furnace and supported above the hearth whereby the traveling charge is treated with a high degree of heat.

6. A furnace comprising an elongated body portion having a hearth therein the whole being mounted on an incline, a supply opening at upper end of said body,- a discharge opening at the opposite end thereof, a plurality of sets of oppositely disposed electrodes projecting laterally through the side walls of the furnace and supported above the hearth, whereby the traveling charge may be treated to a high degree of heat, and means for imparting a transverse rocking motion to the furnace, whereby the material is agitated and advanced through the furnace in a substantially zig-zag path.

7 A new method of treating ores which consists in depositing the material to be treated into a furnace and onto an inclined hearth, rocking the hearth with transverse oscillating movement for agitating 'the material and causin it to move along said hearth, and applying a high degree of heat at a plurality of points to the material 'as it travels down said hearth.

8. A furnace comprising an elongated body portion having a hearth therein and trunnions at its opposite ends, bearings supporting said trunnions and maintaining the furnace in an inclined position, a supply opening at the upper end of the furnace, and a discharge opening at its lower end, whereby the material to be treated is supplied and discharged from the furnace, means connected with the furnace for causing the same to oscillate transversely on the trunnions, and electrodes extending into the furnace from the sides thereof and overlying the material to be treated.

9. A furnace comprising a bed frame, end plates on said frame and recessed on their inner'faces to provide chambers, refractory material supported, by the bed frame and constructed to provide a hollow roasting chamber, the ends of said roasting chamber communicating respectively with the chambers in said end plates, trunnions on the end plates, bearings in which said trunnions engage for supporting the furnace in an inclined endwise position, an elongated entrance opening formed in the uppermost end plate through which material is supplied to the furnace, a discharge opening in the lowermost end plate, and means for imparting a rotary motion to the furnace for agitating the material therein and causing the same to advance through the furnace, and means for subjecting the material in the furnace to a high degree of heat.

In testimon whereof I afiix my signature.

THO AS STANLEY CURTIS. 

